It will only take a few minutes of your time but may prevent a lot of problems. If the manufacturer or someone else requires it just do it - it wont do any harm.
It is assumed that you are asking about bore-hole turbine which are usually submersed in water but here are a few reasons.
A turbine can usually be fitted with a suction extension pipe and if the level is drawn down to below the pump, NPSH calculations is a must.
Because it is usually a multistage pump the contribution of each impeller are not so high. The NPSH.r may therefore not be so good.
The flow-lines at the suction may cause turbulences.
When the pump is started the first time or with a leaking foot-valve the initial flow rate (filling the riser) may be too high.
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Never do today what you can put of until tomorrow - Student motto
Yes, for sure. . . . because you cannort arrive in a full calculated discharge. Vertical turbine design has its advantage in the loss of prime, for it will never occur in this design. But still you need to maintain the level of water available for the calculated head. . . . . or the desired head.
npsh
Re: npsh
